Thousands of pot smokers are expected in Hyde Park this weekend to protest in favour of cannabis legalisation

This Sunday, don’t be alarmed to see a haze drift across west London as thousands of people take a cannabis-shaped leaf out of Snoop’s book and light up in Hyde Park.

As well as being Easter Sunday, the day also marks 420 Day – the international event when pot-smokers around the world join together to protest the cannabis ban in their respective countries; or, in reality, just sit around smoking weed and getting high.

What began as an American pro-cannabis movement has now spread to our shores, with approximately 10,000 people attending the Hyde Park event last year. Although police were in attendance, no participants were arrested for sparking up their spliffs, despite the possession of cannabis still currently an imprisonable offence in Britain. More revellers are expected this time round, with the day conveniently falling before a bank holiday in the UK.

Clear, the group who have recently used advertising vans in London to promote cannabis law reform in the UK, do not support the event. Representative Peter Reynolds suggests that Hyde Park 420 “will give politicians the excuse they need to do nothing,” adding “more than 40 years of demonstrations and rallies have achieved absolutely zilch expect to portray cannabis users as outlaws from society.”

Let's get dealers off the street: the ad vans in Londonvia facebook.com/ClearUK

Others argue, however, that 420 is having a positive effect. The president of UK Cannabis Social Club (UKCSC) believes that “the cannabis community is crying out for legalisation and regulation.” Speaking to the Guardian, Greg de Hoedt, whose UKCSC has also helped organise the event, also said that he has taken note of what is happening worldwide, and would like to make that happen in Britain.

The efforts of 420 may have had a knock-on effect on American cannabis law reform, where 20 states allow the sale of marijuana for medical use. This year saw the first TV advert for weed aired, as well as Colorado and Washington permitting the sale of pot for recreational use. Overseas, Uruguay went one step further: the production and sale of cannabis is now a completely state-run operation.

Whatever the outcome of this Sunday’s Hyde Park 420, it’s probably going to be a very chilled-out protest.